This invention concerns mobility aids, that is, devices for assisting the handicapped and/or infirm to move with a walking action: typical such devices are the stick, the crutch and the so-called "walking frame" and it is with the latter type of mobility aid that the invention is especially concerned.
In its simplest form, a typical walking frame comprises a four-legged tubular metal frame that is generally U-shaped in plan, being open at the rear to permit a user to enter and stand within the frame. It is necessary for the user repeatedly to lift the frame and move it an appropriate distance in the desired direction--an awkward and tiring action that is difficult or impossible for the relatively seriously handicapped or infirm to perform.
It has been proposed to provide the legs of such frames with ground-engaging wheels, casters or gliders and, as a safety feature, such frames may have braking arrangements for preventing movement of the frame upon application of an appropriate download to the frame.
For example, British Patent specification No. 1342397 discloses a walking frame equipped with wheels or casters that are mounted for limited upward movement in the legs of the frame, against the thrust of springs, so that when weight is applied to the frame the wheels move upwardly relative to lugs on the frame legs, the wheels or casters engaging these lugs so as to be braked against rotation.
Further, British Patent specification No. 1373593 describes a similar system using gliders instead of wheels. The gliders have a downwardly spring-loaded sleeve the lower end of which provides a gliding surface and that surrounds a plug of rubber or plastics material providing a gripping surface that is pressed into engagement with the ground when weight is put on the frame so as to cause the sleeve to be pressed upwardly relatively to the plug.
Such wheeled etc. frames are, however, similarly difficult or impossible to use by the relatively seriously handicapped or infirm who need a large degree of support from the frames and must consequently lean very heavily thereon. Furthermore, such frames are not confidence-inspiring to use because of the possibility of the frame "running away" with the user.
It is thus an objective of the invention to provide a walking frame that permits a greater degree of control by the user and that is suitable for use even by the relatively severely handicapped or infirm and capable of greatly enhancing the mobility of such a user.